S77 


METAL  MIXER 


The  easiest,  simplest  and  most  exact  method 

of  mixing  iron  by  chemical  analysis,  with 

tables  and  ready  made  mixtures. 


Indispensable    to    Molders,  Melters  ^ 
and  Foundry  Men. 


W\    IV.   ELLIS 


COPYRIGHT,  1919.         OAKLAND,  CALIF. 

•     - 


GIFT   OF 


THE 

ZMETAL  MIXER 


The  easiest,  simplest  and  most  exact  method 

of  mixing  iron  by  chemical  analysis,  with 

tables  and  ready  made  mixtures. 


Indispensable    to    Molders,   Melters 
and  Foundry  Men. 


W.   W.  ELLIS 


COPYRIGHT,  1919.         OAKLAND,  CALIF. 


CONTENTS 


Introduction  5 

Mixture  for  Medium  Machinery  Castings 9 

Soft  Mixture  for  Pulleys,  Short  Method 12 

Four  Iron  Semi-Steel  Mixtures  for  Rolls 15 

Correcting  Mixtures  with  Ferro-Silicon  or  Ferro-Manganese   1 8 
Semi-Steel  Mixture  for  Rings,  Piston  Valve  Liners,  Gears 

Etc.,  21 

Mixture   for  Marine  Cylinders  Liners 26 

Mixing  with  a  Certain  Per  Cent  of  Steel 29 

Figuring  Three  or  More  Elements  Exact 32 

French  Specifications  for  Semi-Steel  Shells 36 

Side  Lights  on  Mixtures 40 

Miscellaneous  Mixtures „ 43 

Analysis    of   Pig    Irons 44 

Approximate  Grading  Numbers 44 

Approximate  Analysis  of  Important  Castings 45 

The  Influence  Different  Elements  Have  Upon  the  Iron 46 

Percentage  of  Silicon  for  Different  Castings 47 

Judging  Per  Cent  of  Silicon  in  Different  Kinds  of  Scrap 48 

Decimal  Fractions  and  Percentage 49 

Cupola  Practice  54 


395059 

3 


INTRODUCTION, 


In  presenting  this  book  to  molders  and  foundry  foremen 
I  do  so,  believing  there  is  a  real  demand  for  a  book, — 
written  in  plain  every  day  foundry  language  that  anyone 
may  understand,  showing  a  simple  and  easy  method  of  mix- 
ing iron  by  chemical  analysis.  I  have  endeavored  to  explain 
every  mixture  in  a  manner  so  simple,  that  the  man  who  has 
never  mixed  iron,  or  understands  anything  whatever  about 
foundry  work,  can,  with  a  few  minutes  study,  make  any 
kind  of  a  mixture,  from  any  number  of  different  grades  of 
iron,  by  this  easy  method,  almost  as  well  as  the  more  exper- 
ienced foundry  man.  We  do  not  require  a  knowledge  of 
chemistry  to  be  able  to  mix  by  analysis.  In  fact,  the  aver- 
age foundry  man  or  foreman  has  very  little  use  or  time 
for  it.  But  what  we  must  know  is  the  composition  of  the 
iron  we  are  mixing,  and  the  percentage  of  the  different 
elements  it  contains.  The  broker  generally  gives  an  approx- 
imate analysis.  Drillings  should  be  analyzed  for  the  exact 
composition.  In  regard  to  the  influence  and  relation  the 
elements  have  to  one  another,  and  above  all  the  percentage 
of  the  most  important  of  these  elements,  castings  designed 
for  different  kinds  of  work,  should  contain,  I  have  endeavored 
to  explain,  and  if  followed,  will  give  the  reader  a  good  work- 
ing knowledge  of  the  characteristics  of  the  different  elements, 
which  is  a  big  help  in  making  mixtures. 

Foundry  iron  contains  several  of  these  elements,  or  im- 
purities as  they  are  sometimes  called,  but  there  are  only  five 
in  which  we  are  mostly  interested  in.  They  are  silicon, 
phosphorus,  sulphur,  manganese  and  the  carbons.  Of  these 
five,  I  think  the  carbons  are  the  most  important,  because 
carbon  is  the  element  that  gives  the  iron  its  character. 
Foundry  iron  contains  carbon  in  two  distinct  forms,  called 


graphite    carbon  'and   qoiAbi-ied   carbon.      And   according  to 
the   percentage.  ,  of   each  ^of  ,  these   carbons,   so   will   the   iron 
be  hard  or  rof;.     Graphite,;  or   boft  carbon,   is  always  high 
in  very  soft  open  grained  iron.     Combined  or  hard  carbon 
is  always  high  in  very  hard,  close  grained  iron.     In  making 
mixtures  for  the  cupola  it  is  a  more  difficult  proposition  to 
take  hold  of  the  carbons  and  figure  their  content  than  it  is 
silicon  or  some  other  element,  so,  as  a  rule  if  we  wish  to 
reduce  or  change   the  carbons,  we  generally  add  some  low 
carbon  steel  scrap,  or  change  the  carbons  by  using  high  or 
low   silicon    in    the    mixture,    as    the    case   may    require.      In 
making  mixtures  for  the  ordinary  run  of  machinery  castings, 
we   do    not    trouble    about    the    carbons   because   we    find   if 
silicon   is    high,    graphite   carbon    will   be   high    also,    and   if 
silicon  is  lowered,  graphite  carbon  will  be  lower,  and  com- 
bined  carbon   will   be   higher,    and   the   more   we   lower   the 
silicon  the  more   combined  carbon  we  will  get  in  our  cast- 
ings.     Chemists    long    ago    proved,    if   we    wish    to    regulate 
the   carbons   it   can   be   done   through   the   silicon,   which   at 
once   proves    that   silicon   is   one   of   the   most   important,   if 
not  the  most  important  element  the  founder  has  to  work  with. 
Not  only  does  it  influence  the  carbons,  but  the  other  elements 
also,    to    a    certain    extent.      For   we    find   if   we    get   silicon 
normal    for   the    class    of    work    we    are    making,    the    other 
elements   also   will   be   normal,   especially   so,   if  we   use   the 
ordinary  run  of  foundry  irons.     As  the  silicon  can  be  raised 
or  lowered  as  required,  it  is  the  first  element  that  should  be 
figured    in    mixing    iron    by    chemical    analysis.      When    iron 
contains  more  than  3.5  per  cent  silicon,  it  will  begin  to  get 
hard.     Not  hard  and  strong  like  a  low  silicon  close  grained 
iron,  but  hard,   short  and  brittle.     So   in   making   mixtures, 
we  never  go  above  3.25  per  cent  silicon,  and  even  that  per- 
centage  is   very   rarely   used,   except  in   fine   stove  plate,   or 
work  similar  to  it.     There  are  special  mixtures  however,  for 
acid  proof  castings,  that  call  for  a  much  higher  percentage 


of  silicon,  but  these  are  exceptional,  and  are  not  included  in 
the  ordinary  run  of  foundry  products.  Silicon  and  mangan- 
ese are  not  affected  by  mineral  and  vegetable  acids,  like 
graphite  carbon,  sulphur  and  phosphorus  are.  So  in  making 
mixtures  for  this  kind  of  work,  the  combined  carbon,  silicon 
and  manganese  should  be  high,  especially  the  silicon,  which 
of  .course  will  make  the  casting  very  brittle.  To  make  such 
mixtures  takes  considerable  experimenting,  even  by  the 
most  experienced  chemist  and  metallurgist.  In  arranging 
the  different  mixtures  I  have  tried  to  make  them  as  progres- 
sive as  possible.  The  few  mixtures  from  my  note  books, 
I  thought  would  give  the  reader  an  idea  of  what  has  been 
done  with  steel  mixing.  These  were  made  when  pig  iron 
was  very  much  cheaper  than  now,  as  some  were  made  as  far 
back  as  1904.  The  analysis  of  different  pig  irons  will  also 
give  beginners  a  working  idea  of  the  composition  of  iron. 
The  few  remarks  on  the  influence  the  different  elements  have 
upon  the  iron  will  all  help  the  student  how  to  use,  and  mix 
them  to  accomplish  a  certain  purpose. 

In  selecting  and  using  scraps,  of  course  is  more  or  less 
guess  work.  But,  by  careful  study  and  selection,  and  by 
getting  a  determination  now  and  then,  one  will  soon  be  able 
to  judge  the  silicon  content  for  all  practical  purposes.  But 
if  special  work  is  to  be  made  to  specification,  such  as  shells 
or  other  governmental  work,  all  the  scraps  must  be  melted 
and  pigged,  and  analysis  taken  of  each  cast.  Only  then  can 
we  say  with  confidence,  just  what  is  the  composition  of  the 
scrap. 

In  the  mixtures  showing  the  method  of  mixing  three 
or  more  irons  together,  I  have  used  a  higher  per  cent  of 
steel  than  I  would  advise  to  use  without  experience.  Although 
I  have  made  mixtures  containing  more  than  25  per  cent  steel, 
still  I  am  convinced  by  actual  tests,  that  no  improvement 
or  benefit  can  be  obtained  by  using  more.  This  opinion 
seems  to  be  general  among  other  foundry  men,  who  have  had 


any  experience  with  steel  and  iron  mixtures.  I  have  also 
found  if  using  a  higher  per  cent  the  best  results  was  obtained 
when  using  all  pig  and  steel  scrap.  Steel  mixtures  must  be 
melted  hot  and  handled  quick  when  in  the  ladle.  The  few 
examples  on  decimals  and  percentage  will  help  refresh  our 
memories,  and  are  handy  to  refer  to  while  studying  this 
method,  as  they  deal  directly  with  the  work  of  the  book.  The 
last  chapter  deals  with  the  cupola,  which  are  chiefly  personal 
experiences,  and  agrees  closely  with  our  leading  foundry  men. 
And  if  followed  as  near  as  possible  together  with  other  in- 
formation in  the  book,  the  young  foundry  man  should  have 
no  trouble  in  handling  the  mixing  and  melting  end  of  any 
shop,  independent  of  the  class  of  work  being  made. 

— W.  W.  ELLIS. 


MIXTURE  FOR  MEDIUM  MACHINERY 
CASTINGS. 

In  this  mixture  we  will  figure  for  silicon  only,  and  I 
would  advise  the  student  to  work  over  this  first  mixture  until 
you  understand  it.  You  will  then  be  surprised  how  simple  it 
is.  You  will  then  have  the  foundation  for  making  any  kind 
of  a  mixture  from  any  number  of  different  grades  of  iron. 
A  mixture  for  medium  machinery  work  should  contain  about 
2  per  cent  silicon,  with  that  percentage,  castings  from  54- 
inch  in  section  should  machine  quite  easy.  As  we  lose  about 
two  tenths  (0.2)  of  one  per  cent  silicon  in  melting,  we 
must  add  that  much  to  our  mixture  before  it  goes  into  the 
cupola.  On  account  of  this  loss  we  must  figure  our  mixture 
to  contain  2.2  per  cent  silicon.  To  make  this  we  will  use 
pig  iron  and  scrap  enough  to  make  a  mixture  of  2000  pounds. 
The  pig  contains  3.25  per  cent  silicon,  and  the  scrap  1.75 
per  cent.  As  we  desire  only  2.2  per  cent,  you  will  notice 
that  I  have  selected  one  iron  with  a  higher,  and  one  with 
a  lower  per  cent  of  silicon.  We  will  now  put  the  lowest 
silicon  under  A,  the  amount  we  desire  under  B,  and  the 
highest  silicon  under  C.  So  placing  them  in  that  order  they 
stand  as  follows:  A.  B.  C. 

1.75    2.20     3.25 

RULE:  By  subtracting  A  from  B  we  get  .45  remain- 
der; substracing  B  from  C  we  get  1.05.  We  now  add  both 
remainders  together,  getting  1.50.  Taking  the  first  remain- 
der .45  and  after  affixing  two  ciphers  to  it,  and  moving 
the  decimal  point  two  places  to  the  right,  and  dividing  it 
by  the  sum  of  the  two  remainders  1 .50,  we  get  30,  the 
percentage  of  the  C  iron  to  be  used  in  the  mixture.  Taking 
the  second  remainder  1.05,  and  after  affixing  two  ciphers, 
and  moving  the  point  two  places  to  the  right,  dividing  it 
also  by  1.50  we  get  the  percentage  of  the  A  iron,  which  is 
70, — to  be  used  in  the  mixture. 


Example 

Take   A   from   B. 

1st  Remainder 
Add  both  remainders 

Sum  of  the  two 


A. 
1.75 

rs 

B. 
2.20 
1.75 

C. 

3.25 
2.20 

.45 
1.05 

1.05 
1 

1.50 
TABLE  No. 

Take  B  from  C. 
2nd  Remainder 


1st  remainder   .45   representing  C  iron. 
Two   ciphers   affixed   and  point   moved   two  places   and 
divided  by         1.50)45.00(30%   of  C  iron  to  be  used. 
45.00 

TABLE  No.  2 

2nd    Remainder    1.05    representing   A    iron.      With    two 
ciphers    affixed   and   point   moved   two  places   we   divide   by 
1.50)1 05 .00(   70%  of  A  iron  to  be  used  in  the  mixture. 
10500 

TABLE  No.  3 

Don't  miss  this  one  point  of  setting  the  different 
silicons  under  their  proper  heading. 

Always  set  the  lowest  silicon  under  A,  what  we  desire 
under  B  and  the  highest  under  C.  Then  take  A  from  B,  and 
the  first  remainder  will  always  represent  the  C  iron.  Then 
take  B  from  C  and  the  second  remainder  will  always  represent 
the  A  iron.  As  these  remainders  only  represent  the  A  and 
C  irons,  they  do  not  tell  us  how  much  per  cent  of  each  one 
to  take.  To  find  a  rate  so  we  can  figure  what  percentage 
of  these  two  irons  to  use,  we  add  these  two  remainders 
together,  and  after  affixing  two  ciphers  to  each  one,  we 
divide  each  one  by  the  base,  or  sum  of  the  two.  The  result 
of  this  division  is  of  course  the  percentage  of  the  iron  we 
are  to  use  that  each  remainder  represent,  which  is  clearly 
shown  in  tables  2  and  3.  When  affixing  the  two  ciphers  to 

10 


each  of  the  remainders,  be  sure  and  move  the  decimal  point 
two  places  to  the  right  even  though  it  does  point  off  ciphers 
as  in  this  example. 

We  will  now  check  off  our  mixture. 

According  to  our  figures  we  are  to  use  30  per  cent  of 
C  iron,  and  70  per  cent  of  A  iron.  By  multiplying  the 
3.25  per  cent  of  silicon  by  the  30  per  cent,  we  get  .9750 
per  cent,  and  by  multiplying  the  1.75  per  cent  by  the  70 
per  qent  we  get  1.2250  per  cent.  Adding  these  two  per- 
centages together  will  give  us  our  desired  percentage  of 
2.2  per  cent  silicon. 

Example: —     Percentage  of  silicon  in  C  iron  3.25 

Percentage  of  C  iron  to  be  used  .30 


Per  cent  of  silicon  .9750 

TABLE  No.  4 

Percentage  of   silicon   in   A   iron  1.75 
Percentage  of  A  iron  to  be  used  .70 


Per  cent  of  silicon  1.2250 

Percentage  of  silicon  from  C  iron  .9750 


The  required  per  cent  amount  of  silicon     2.2000 

TABLE  No.  5 

This  method  gives  the  percentage  of  silicon  as  well  as 
the  percentage  of  the  iron. 
Example :  — 

30  per  cent  of  2,000  Ibs.  =     600  Ibs.  of  C.    pig  iron. 
70  per  cent  of  2,000  Ibs.  =   1400  Ibs.  of  A  scrap  iron. 

Mixture  of  2000  Ibs. 

TABLE  No.  6 

In  tables  2  and  3  the  divisors  and  dividends  has  each 
two  decimal  places  which  make  the  quotients  whole  numbers, 
— see  decimals. 

11 


SOFT  MIXTURES  FOR  PULLEYS 

We  will  make  this  another  two  iron  mixture,  and  figure 
for  silicon  only,  introducing  shorter  method  with  less  figuring. 
In  making  mixtures  for  pulleys,  we  should  try  and  keep  the 
silicon  three  or  four  points  higher  than  we  would  for  castings 
in  our  first  mixture.  The  metal  will  be  softer  and  of  course 
the  shrinkage  will  be  lower.  Even  with  this  percentage,  all 
pulley  hubs  should  be  stripped  and  cores  taken  out. 

Suppose  we  want  a  mixture  of  1500  pounds  containing 
2.4  per  cent  silicon  in  the  castings.  That  means  with  the 
loss  of  silicon  in  melting  our  mixture  must  contain  2.6  per 
cent  before  going  into  the  cupola.  To  make  this  mixture 
we  will  use  some  of  the  gates  of  our  first  mixture  containing 
2.0  per  cent  silicon,  and  No.  1  Sloss  pig  iron  containing  3.6 
per  cent  silicon.  Putting  the  lowest  silicon  under  A,  our 
desired  under  B  and  the  highest  silicon  under  C.  We  then 
work  out  as  in  table  No.  1 . 

By  substracting  A  from  B  we  get  our  first  remainder  .6, 
which  represents  the  C  iron  to  be  used  in  the  mixture.  Sub- 
stracting B  from  C  we  get  our  second  remainder,  1 .0  which  rep- 
resents the  A  iron  to  be  used  in  the  mixture.  After  adding 
these  two  remainders  together  and  getting  1 .6,  we  take 
the  first  remainder  and  after  affixing  two  ciphers  to  it,  we 
move  the  decimal  point  two  places  to  the  right,  making 
60.0.  We  now  divide  the  60.0  by  the  sum  of  the  two  re- 
mainders 1.6;  which  we  find  goes  37J/2  times.  As  this  first 
remainder  represents  the  C  iron,  it  shows  we  are  to  take 
37.5  per  cent  of  C  iron  to  use  in  our  mixture.  Now,  if  we 
are  to  use  37.5  per  cent  of  C  iron,  it  stands  to  reason  we 
must  use  62.5  per  cent  of  A  iron,  as  37.5  and  62.5  equals 
100.  So  that  being  the  case,  further  figuring  are  unneces- 
sary. Example : 


12 


A.       B.        C. 
2.0       2.6      3.6 
Take  A  from  B  2.0       2.6         Take  B  from  C. 


1  st  remainder  .6       1 .0  2nd  remainder 

Add  both  remainders  1.0 


Divide  by  1 .6)60.00(37.5  %  of  C  iron. 

48 


120 

112      62.5  %  of  A  iron. 


80 
80 

TABLE  No.  7. 

You  will  notice  instead  of  making  two  separate  tables 
as  in  our  first  mixture,  we  simply  take  the  first  remainder  .6 
put  it  to  the  right  of  the  1.6,  add  two  ciphers  to  it,  and 
move  the  point  two  places,  then  divide  it  by  the  1.6.  The 
result  of  this  division  completes  all  the  figures  required  to  get 
the  percentage  of  the  irons  to  be  used  in  any  mixture,  so 
make  yourself  familiar  with  the  first  mixture,  then  you 
will  be  able  to  follow  table  7  with  ease.  For  table  7  is  the 
form  in  which  you  will  make  all  your  mixtures  in  actual 
practice,  except,  of  course,  when  correcting  mixtures,  or 
mixtures  that  have  even  number  remainders,  which  will  be 
explained  in  other  mixtures  following. 

Percentage  of  silicon  in  C  iron  3.6 

Percentage  of  C  iron  to  be  used  37.5 


Per  cent  of  silicon  1.3500 

13 


TABLE  No.  8 

Percentage  of  silicon  in  A  iron  2. 

Percentage  of  A  iron  to  be  used  62.5 


Per  cent  of  silicon  1 .250 

Silicon  from  C  iron  1.350 


The  per  cent  amount  of  silicon  required  2.600 

TABLE  No.  9 

37.5  per  cent  of   1500  =  562.5   pounds  of  C  pig  iron. 
62.5  per  cent  of   1500  —  937.5   pounds  of  A  gate  scrap. 


Charge  of   1500.0  pounds 
TABLE  No.  10. 

Note:  In  multiplying  by  the  rate  for  percentage,  you 
point  off  two  for  the  whole  numbers,  and  as  many  decimals 
as  there  are  in  the  multiplier  and  multipliant,  which  makes 
four  in  table  8,  and  three  in  table  9.  See  decimals.  In 
actual  practice  we  would  only  require  tables  7  and  10. 
Tables  8  and  9  are  merely  used  to  prove  our  figures. 


14 


MIXTURE  FOR  A  ROLL  SEMI-STEEL  USING  FOUR 
DIFFERENT  KINDS  OF  IRON 


In  this  mixture  we  will  explain  a  method  whereby  any 
number  of  different  kinds  of  iron  can  be  mixed  together. 

When  making  a  mixture  to  contain  several  different 
brands  of  iron,  and  not  being  particular  how  much  of  each, 
the  best  way  is  to  segregate  them,  putting  all  the  irons 
together  that  contain  a  lower  silicon  than  we  require  in  our 
mixture  into  one  group,  and  all  the  irons  that  contain  a 
higher  per  cent  of  silicon  into  another  group.  After  getting 
the  mean  percentage  of  silicon  from  each  of  these  groups, 
we  have  practically  but  two  irons  to  figure  on,  and  can  be 
worked  out  as  in  table  7.  Then,  after  we  have  found  what 
percentage  of  each  group  we  are  to  use,  we  must  divide 
each  percentage  into  as  many  parts  as  there  are  irons  com- 
posing each  group. 

Example:  Suppose  we  wish  a  mixture  of  4,000  pounds 
for  a  20  inch  dia-chilled  roll,  containing  0.6  per  cent  silicon, 
adding  the  usual  0.2  per  cent  for  loss  of  silicon,  would  make 
our  desired  silicon  0.8  per  cent  before  it  goes  into  the 
cupola.  To  make  this  mixture  we  will  use  some  of  the 
following  irons. 

Sil.  Phos.  Sul.  Mang.  T.  C. 

Heavy  scrap  1.50  0.40  0.08  0.60 

Salisbury  pig  1.29  0.30  0.045  0.40  3.85 

Steel  scrap  0.2  0.05  0.05  0.50  0.10 

Cargo  fleet-pig  0.79  1.52  0.027  0.23  3.12 

TABLE  No.  11. 

By  putting  the  two  lowest  silicons  together  and  dividing 
them  by  2.  we  find  their  mean  silicon  content  is  0.495  per 
cent,  which  must  be  put  down  under  A.  Putting  the  two 
highest  silicons  together  and  dividing  them  also  by  2,  we 

15 


find  their  mean  silicon  content  is  1 .395  per  cent,  which  must 
be  put  clown  under  C.  The  desired  silicon  of  course  must 
be  put  down  under  B.  This  gives  us  practically  a  two  iron 
mixture,  and  they  stand  ready  to  be  figured  as  in  table  No.  7. 

A.  B.  C. 

0.495      0.800        1.395 
Take  A  from  B  .495  .80       Take  B  from  C. 


1  st  Remainder  .305  .595     2nd  Remainder. 

Add  both  .595 


Divided  by  .900) 30.500 (  33-8/9%  of  C  iron 

2700      66-1/9%  of  A  iron 


3500 
2700 


800 

equals  8/9 


900 

TABLE  No.  12. 

Table  No.  12  shows  we  are  to  take  33-8/9  per  cent  of 
C  iron.  Then,  of  course  we  must  take  66-1/9  per  cent  of 
A  iron. 

As  each  of  these  percentages  have  to  be  divided  into 
two  equal  parts,  we  will  do  away  with  the  fractions,  and 
call  each  one  a  whole  number,  which  will  save  extra  figuring 
and  will  not  affect  the  result  any.  By  making  them  whole 
numbers  we  have  34  per  cent  of  C  iron  and  66  per  cent 
of  A  iron.  As  the  C  iron  is  composed  of  heavy  scrap  and 
Salsbury  pig,  we  must  use  1 7  per  cent  of  each,  and  of 
course  33  per  cent  of  each  of  steel  and  Cargo  Fleet.  In 
checking  them  off  at  these  rates,  we  find  we  have  a  shade 
more  silicon  than  we  desire,  brought  about  of  course  by 
using  all  whole  numbers  instead  of  the  fractions. 

16 


Example : 

17%  of   1.50%   silicon  in  Heavy  scrap,  equals  0.2550% 

17%   of   1.25%   silicon  in  Salisbury  scrap,  equals  0.2193% 

33%   of  0.20%   silicon  in  Steel  scrap,  equals  0.0660% 

33%  of  0.79%   silicon  in  Cargo  Fleet-pig,  equals  0.2607% 


100  Total  silicon  equals     0.8010% 

Loss  in  melting     0.20 


0.6010% 
TABLE  No.  13 

17%  of  4000  pounds  equals  680  pounds  Heavy   scrap. 

1 7%  of  4000  pounds  equals  680  pounds  Salisbury    pig. 

33%  of  4000  pounds  equals  1320  pounds  Steel   scrap. 

33%  of  4000  pounds  equals  1320  pounds  Cargo  Fleet-pig. 


Charge  of     4000  pounds 
TABLE  No.  14 

To  multiply  one  percentage  by  another  percentage,  see 
percentage. 

In  shop  practice  when  this  method  is  understood,  we 
would  require  only  tables  12  and  14,  saving  the  figuring  of 
table  13,  which  we  know  would  be  correct. 

The  other  elements  can  be  figured  the  same  way  as 
silicon.  The  manganese  which  would  be  low  for  a  casting 
of  this  kind,  could  be  corrected  with  ferro-manganese,  as 
explained  in  following  mixtures. 


17 


METHOD  FOR  CORRECTING  MIXTURES  WITH  FERRO- 
SILICON  OR  FERRO-MANGANESE. 


This  method  is  useful  when  we  wish  to  add  more  silicon 
or  manganese,  as  the  case  may  be,  to  a  mixture  already 
figured. 

We  wish  to  make  a  mixture  of  2000  pounds  for  medium 
floor  work  containing  2.2  per  cent  silicon.  We  have  1000 
pounds  of  foundry  scrap  which  we  know  contains  2  per  cent 
silicon  and  1000  pounds  of  heavy  scrap  containing  1.5  per 
cent  silicon.  As  these  two  lots  of  iron  are  the  amount  we 
require  in  our  mixture,  we  will  see  how  much  silicon  they 
will  bring  into  it.  50  per  cent  of  2  per  cent  silicon  in 
foundry  scrap  gives  us  1.0  per  cent,  and  50%  of  1.5%  silicon 
in  heavy  scrap  gives  us  0.75%  more,  making  a  totoal  of  1.75 
per  cent  silicon,  leaving  0.45  per  cent  more  to  be 
supplied  by  the  ferro-silicon  to  make  our  mixture  contain  2.2 
per  cent.  This  0.45  per  cent  is  what  we  want,  and  must  go 
down  under  B.  The  ferro-silicon  containing  80  per  cent 
silicon  must  be  put  down  under  C,  and  as  we  are  working 
with  one  iron  only,  we  will  put  a  cipher  under  A.  Setting 
them  down  in  that  order,  they  stand  ready  to  be  figured  as 
in  table  7. 


18 


Example : 


A. 


Take  A  from  B 

1  st  Remainder 
Add  both 

Divided  by 


0 


B. 

.45 
0 


C. 

80.00 

.45  Take  B  from  C. 


.45 
79.55 


79.55     2nd  Remainder. 


80.)45.0000(.5625%  of  C  Per.  sil. 
400 


500 
480 

200 
160 


400 
400 
TABLE  No.  15 

2000  Pounds 
00.5625 


11.250000  Pounds 
TABLE  No.  16 

11.25  Pounds 
.80 


20)9.0000(.45% 
80 


100 
100 

TABLE  No.  1 7 


19 


80 
00.5625 

.450000%  of  silicon  from  Ferro  Silicon 
1 .75          %  of  silicon  from  scrap  iron 


2.20  Total  silicon. 

TABLE  No.  18 

Table  15  shows  we  are  to  add  0.5625  per  cent  of  ferro 
silicon  to  the  mixture.  To  find  the  amount  of  ferro-silicon 
in  pounds  we  are  to  use,  we  will  multiply  the  2000  pounds  of 
iron  by  .5625%  making  it  11.25  Ibs.  Multiply  11.25  pounds 
by  the  per  cent  of  silicon  it  contains  (which  is  80,)  and 
dividing  the  result  by  20,  the  number  of  hundred  pounds  in 
the  mixture  will  give  us  our  required  silicon  0.45  per  cent. 
Or,  multiply  the  80  per  cent  ferro-silicon  by  the  percentage 
we  are  to  take,  .5625,  will  also  give  us  our  required  0.45 
per  cent.  See  tables  16,  17  and  18  above.  I  have  used 
80  per  cent  ferro-silicon,  it  serves  our  purpose  as  well  as 
50%  or  any  other  per  cent. 


20 


THREE  IRON  SEMI-STEEL  MIXTURES  WITH  APPROXI- 
MATE FIGURING  OF  ALL  THE  ELEMENTS. 


This  mixture  if  melted  hot  and  under  proper  conditions 
would  be  suitable  for  marine  piston  rings,  piston  valve  liners, 
cut  and  cast  gears,  etc.  Although  we  are  using  high  steel  in 
this  mixture  it  is  advisable  not  to  attempt  high  steel  mixtures 
without  previous  experience.  In  making  a  mixture  of  this 
kind,  there  are  always  two  elements  we  are  sure  of  getting 
exact.  These  are  silicon  and  manganese,  which  will  be 
proved  in  this  mixture.  The  other  elements  will  be  influenced 
by  these  two,  and  can  be  made  normal  for  the  mixture,  es- 
pecially so,  if  we  select  irons  suitable  for  the  work  in  hand. 

Keep  the  sulphur  and  phosphorus  low.     If  the  sulphur 
is  high,  raise  the  manganese  a  point  or  two.     We  will  make 
a  mixture  of  2000  pounds  to  contain 
Silicon         Phos.         Sulphur         Mang.         Total  Carbon 
1.8%      0.45%        0.07%         0.75% 

From  the  following  irons: 

Buckeye   3.6%     0.55%  0.016%     0.50%    3.50% 

Scrap  iron  2.2         0.60         0.070       0.45          3.25 

Scrap  steel   0.2         0.05          0.050       0.50         0.08 

TABLE  No.  19. 

As  we  are  not  particular  what  per  cent  of  each  iron 
we  use,  the  best  way  is  to  put  the  two  lowest  silicon's 
together,  and  get  their  mean  percentage.  In  this  case  we 
will  put  scrap  iron  and  scrap  steel  together.  So  adding  2.2 
and  0.2  together  making  2.4  per  cent  silicon,  and  dividing 
by  2.  will  give  us  their  mean  per  cent,  1.2.  This  gives 
us  now,  practically,  but  two  irons  to  figure  on.  Putting 
them  under  their  proper  headings  they  stand  ready  to  be 
figured  as  in  table  7.  Adding  0.2  for  loss  of  silicon  in 
melting  will  make  our  desired  2.0%. 

21 


Take  A  from  B 


A. 

1.2 


1st] 


nder 


B. 

2.0 
1.2 

.8 


C. 

3.6 

2.0 


Take  B  from  C. 


1 .6     2nd  remainder 


TABLE  No.  20 


When  one  remainder  is  just  twice  as  much  as  the  other, 
it  shows  we  are  to  take  33 Vz  per  cent  of  the  C  iron,  and 
66//3  per  cent  of  the  A,  and  no  more  figuring  are  required. 
If  both  remainders  should  come  the  same  it  would  mean  50 
per  cent  of  each  A  and  C,  and  if  one  remainder  should 
happen  to  come  three  times  as  much  as  the  other,  we  would 
have  to  take  75  per  cent  of  one,  and  25  per  cent  of  the 
other.  In  this  case  we  are  to  take  33^  per  cent  of  C  and 
66^  per  cent  of  A  iron.  As  the  A  iron  is  composed  of  scrap 
iron  and  scrap  steel,  it  means  we  are  to  use  33 Vz  per  cent  of 
each  pig  iron,  scrap  iron  and  steel.  In  checking  off  at  these 
percentages  we  get  the  following  results: 

Example — 

Silicon. 

Pig   iron  33J/3%  of  3.6%  silicon  equals      1.200     % 

Scrap   iron  33J/3%  of  2.2%  silicon  equals     0.733/  % 

Scrap  steel  33/3%  of  0.2%  silicon  equals     0.066^% 

A—  Total  silicon  2.000     % 

Loss  in  melting  equals  0.2          % 

Silicon  in  casting  1 .8         % 
Phosphorus. 

Pig  iron                331/3%  of  0.55%  phos.,  equals  0.1833/3  % 

Scrap  iron            33J/3%  of  0.60%  phos.,  equals  0.2000 

Scrap    steel           33/3%  of  0.05%  phos.,  equals  0.01662/ 


Phosphorus  does  not  lose  or  gain  in  melting 

22 


.4000     % 


B— 
Pig    iron 
Scrap  iron 
Scrap   steel 

Sulphur. 
33J/3%  of  0.016%  sulp.,  equals     0.00533  Vz% 
33|/3%  of  0.07   %  sulp.,  equals     0.02330/3 
33]/3%of0.05   %sulp.,  equals     0.0166  ^ 

Gain  in  melting  equals 

.045241/3 
.03 

C  —                                       Manganese. 

Pig   iron            33J/3%  of  0.50%  mang.,  equals 
Scrap  iron       33]/3%  of  0.45  %  mang.,  equals 
Scrap  steel       33^3%  of  0.50%  mang.,  equals 

Loss  in  melting,  equals 
Manganese  from  80%   ferro-mang.,  equals 

D  —                                  Total  Carbon. 

Pig  iron              33^3%  of  3.50%  carbon,  equals 
Scrap    iron        33  J/3%  of  3.25%  carbon,  equals 
Scrap  steel         33J/3%  of  0.08%  carbon,  equals 

E  —                                                    Total  carbon 

Pig    iron                   33|/3%  of  2000  Ibs.,  equals 
Scrap  iron                33J/3%  of  2000  Ibs.,  equals 
Scrap   steel               33J/3%  of  2000  Ibs.,  equals 

.07524/3% 

0'.150 
OA662/3 

0.483/3 
0.100 

0.383 
0.367 

0.750    % 

1.16662^% 
1.0743/3 

2.26762^% 

6662/3  Ibs. 
6662/3  Ibs. 
6662/3  Ibs. 

F— 


2000  Ibs. 


TABLE  No.  21. 


This  table  shows  that  all  the  elements  are  nearly  as  we 
want  them,  except  the  manganese,  which  of  course  can  be 
corrected  to  what  we  require  with  ferro-manganese.  The 

23 


sulphur  is  slightly  higher,  but  the  high  manganese  will  be 
liable  to  offset  that  much.  As  we  desire  0.75  per  cent 
manganese  in  our  mixture  and  our  irons  have  given  us  only 
0.383  per  cent,  it  is  evident  we  must  get  0.367  per  cent 
from  the  ferro-manganese. 

To  find  the  number  of  pounds  of  ferro-manganese  to 
use,  so  as  to  get  this  0.367  per  cent  manganese  in  the  mix- 
ture, we  will  set  the  80  per  cent  under  C,  the  desired  0.367 
under  B,  and  figure  out  as  in  table  15  on  correcting  mix- 
tures or,  using  a  shorter  method  which  can  always  be  done 
when  figuring  a  one  iron  mixture  like  this,  we  will  simply  affix 
two  ciphers  to  B,  move  the  point  two  places  to  the  right, 
then  divide  it  by  C.  Example:  — 

TABLE  No,  22.          w*          TABLE  No.  23 


A.  B.  C.  <f*  80 

0.          .367          .80  .45% 

80)36.700(.457/8%  ^T~ 

320 


470 


320 


400  .3670% 


70 


-=7/8 


80 

TABLE  No.  24 

2000  pounds 
•457/8 


1750 
10000 
8000 

9.1750  pounds 
3    24 


If  you  will  look  over  Table  22,  you  will  see  we  have 
accomplished  the  same  results  as  we  did  in  table  15,  with 
considerable  less  figuring.  The  figures  show  we  are  to  use 
45%%  of  ferro-manganese.  Multiplying  80  per  cent  man- 
ganese by  the  .45%%,  gives  us  our  required  0.367%,  as  in 
table  23,  and  to  get  the  number  of  pounds  of  fero-manganese 
we  are  to  use  to  get  this  percentage  of  manganese,  we  mul- 
tiply the  full  charge  of  2000  pounds  by  the  .45%%,  which 
shows  we  are  to  use,  9.175  pounds  of  ferro-manganese  as  in 
table  24.  By  multiplying  the  9.175  pounds  by  the  80%, 
will  give  us  the  exact  number  of  pounds  of  manganese, 
we  will  get  from  the  fero-manganese  which  is  7.34  pounds. 
Now  divide  this  7.34  by  20,  the  number  of  100  pounds  in 
the  mixture,  will  again  give  us  our  required  per  cent,  0.367 
of  manganese,  as  in  table  25. 

Example :  — 

9.175 
80 
20)  7.34000 (.367%  manganese. 


60 


134 
120 

140 
140 

TABLE  No.  25 

Manganese  from  pig  iron  and  scrap,  equals  0.383% 

Manganese   from  80%    Ferro-Manganese,   equals         0.367% 


Manganese   in   mixture  0.750% 

In  shop  practice  the  per  cent  of  D  and  F  in  table  No. 
21,  and  tables  22  and  24  is  all  we  need  figure.  The  other 
tables  are  worked  merely  to  prove  the  mixture. 

25.. 


MIXTURE  FOR  LARGE  CYLINDER  LINERS,  ETC. 

Show  Methods,  if  a  Certain  Per  Cent  of 

Some  of  the  Irons  Are  to  be  Used 


We  will  make  a  mixture  of  2000  pounds  to  contain  1.0 
per  cent  silicon.  We  must  use  500  pounds  of  steel  scrap 
containing  0.2  per  cent  silicon,  and  500  pounds  of  liner 
scrap  containing  1.0  per  cent  silicon.  We  have  besides  some 
scrap  containing  1 .6  per  cent  silicon,  and  pig  iron  containing 
2.2  per  cent  silicon.  By  adding  the  0.2  per  cent  silicon  to 
make  up  for  loss  in  melting,  our  mixture  will  have  to  con- 
tain 1.2  per  cent  silicon.  The  first  thing  to  do  when  making 
a  mixture  with  a  given  per  cent  of  some  of  the  irons  is  to 
find  how  many  pounds  of  silicon  the  mixture  must  contain. 
Here  we  want  2000  pounds  to  contain  1 .2  per  cent  silicon, 
multiplying  the  2000  by  the  1 .2  per  cent  gives  us  24  pounds 
of  silicon.  This  is  the  amount  we  must  get  in  this  mixture. 
The  next  is  to  find  how  much  the  given  irons  will  contribute 
to  the  24  pounds,  multiplying  500  pounds  of  steel  by  0.2 
per  cent  will  give  us  1  pound  of  silicon.  The  500  pounds  of 
liner  scrap  containing  1 .0  per  cent  will  contribute  5  pounds 
more.  This  makes  6  pounds,  leaving  18  pounds  more  for  the 
other  1000  pounds  of  iron  to  bring  in.  Now,  if  we  had 
some  1 .8  per  cent  silicon  iron,  1 000  pounds  of  that  would 
just  make  our  mixture  complete,  by  giving  us  the  18  pounds 
of  silicon  we  require.  And  of  course  no  more  mixing  would 
be  necessary,  but  we  have  only  1 .6  per  cent  scrap,  and  the 
2.2  per  cent  pig  iron.  So  we  must  find  how  much  of  each  of 
these  we  must  use  to  complete  the  mixture.  As  we  want 
1000  pounds  more  iron,  and  18  pounds  of  it  must  be  silicon, 
that  means  it  must  contain  1.8  per  cent  silicon,  which  of 
course  is  our  desired  silicon,  and  must  be  put  under  B,  set- 
ting them  down  under  their  proper  headings,  they  stand  ready 
to  be  figured  as  in  table  1.  Example:  — 

26 


A.  B.  C. 

-1.6          1.8         2.2 
Take  A  from  B  1.6  1.8  Take  B  from  C. 


1st  Remainder  .2  .4     2nd    Remainder. 

TABLE  No.  26. 

As  we  have  shown  in  previous  mixtures,  when  one 
remainder  is  as  much  again  as  the  other,  it  means  we  are 
to  take  33J/3%  of  the  iron  the  smallest  remainder  represents, 
(which  is  C),  and  66^/3%  of  the  iron  that  the  largest  rep- 
resents— which  is  A.  As  we  only  want  1000  pounds  more 
iron  to  complete  the  mixture  this  means  we  are 
to  take  3331/3  pounds  of  pig  iron,  666^/3  pounds  of 
scrap  iron.  By  taking  the  500  pounds  of  steel,  500  pounds 
of  liner  scrap,  333J/3  pounds  of  pig  iron,  666^/3  pounds 
of  scrap  iron,  and  multiply  each  one  by  the  per  cent  of 
silicon  it  contains,  will  give  us  the  24  pounds  of  silicon  we 
require  in  the  mixture.  Example:  — 

Steel  500      pounds  x  0.2%   equals      1        Ib.  silicon 

Liner  scrap         500      pounds  x  1 .0%  equals     5       Ib.  silicon 
Pig  iron  333J/3  pounds  x  2.2%   equals     7J/3  Ib.  silicon 

Scrap  666^/3  pounds  x  1 .6%   equals   10^/3  Ib.  silicon 


20)24.0(1. 2%  sil. 
20 


40 
40 


TABLE  No.  27. 


By  dividing  the  24  pounds  by  the  number  of  100  pounds 
in  the  mixture,  (which  is  20),  gives  us  our  required  1.2  per 
cent  silicon.  Here  is  another  way  to  check  it  off,  but  as 
we  were  only  figuring  for  half  the  mixture  in  table  26,  we 
must  take  only  half  of  each  percentage  thus  obtained,  mak- 

27 


ing  it  162/3%  of  pig,  or  "C"  iron,  and  33J/3%  of  the  scrap, 

or  "A"  iron.     Example:  — 

Steel  25%  of  0.2%   silicon  equals     0.050%  silicon 

Liner  scrap       25%  of   1.0%  silicon  equals 

Pig    iron        162/3%  of  2.2%   silicon  equals 

Scrap  33J/3  %  of   1.6%   silicon  equals 


0.250%  silicon 
0.366^  silicon 
0.533%  silicon 


1.200%  silicon 


TABLE  No.  28. 


By  using  this  same  percentage,  the  other  elements  if 
known,  can  be  figured  as  in  table  No.  21.  And  the  Man- 
ganese corrected  as  in  tables  22,  23  and  24. 

Any  number  of  different  grades  of  iron  can  be  mixed 
this  way.  Always  leaving  two  irons, — one  with  lower  and 
one  with  a  higher  silicon  content  than  we  desire  to  corect 
the  mixture  with. 


28 


METHOD  OF  FIGURING  WHEN  A  CERTAIN  PER  CENT 
OF  STEEL  MUST  BE  USED. 


This  mixture  would  be  suitable  for  heavy  gas  and 
hydraulic  cylinders  and  other  castings  that  require  strength 
and  close  grained  enough  to  stand  water  pressure.  We  wish 
a  25  per  cent  steel  mixture  of  2000  Ibs.,  to  contain  1 .6  per 
cent  silicon,  and  0.75  per  cent  manganese.  We  will  use  12 
per  cent  manganese  scrap  steel  to  corect  the  manganese 
with,  we  will  use  the  following  irons: 

Silicon  Phos.         Sulp.         Mang. 

Pig  iron  3.00%        0.5%        0.016%        0.5% 

Scrap  iron  1.8  0.5  0.08  0.4 

Scrap  steel  0.0  0.02  0.05  0.5 

TABLE  No.  29 

By  adding  0.2  per  cent  silicon,  and  0.1  per  cent  man- 
ganese for  loss  while  melting,  will  make  our  required  silicon 
1.8  per  cent,  and  the  manganese  0.85  per  cent.  When  mak- 
ing a  mixture  of  this  kind,  I  figure  to  get  all  the  silicon  from 
the  iron,  because  of  the  small  amount  of  silicon  in  the  steel. 
On  account  of  having  to  get  all  the  silicon  from  the  1500 
pounds  of  iron,  that  of  course  changes  our  desired  silicon 
for  the  present,  because  the  1500  pounds  of  iron  will  have 
to  carry  enough  silicon  to  give  1 .8  per  cent  to  the  full 
charge  of  2000  pounds  of  both  iron  and  steel.  To  get  this 
new  required  per  cent  of  silicon,  we  will  divide  the  percent- 
age of  silicon  required  in  the  whole  charge,  by  the  per  cent 
of  the  iron  used, — which  is  75  per  cent.  Please  take  note 
of  this  rule.  Example:  — 

TABLE  No.   30  TABLE  No.   31 

.75)1.800(2.4%    silicon.  A.        B.        C. 

150  1.8      2.4      3.0 

1.8      2.4 

300  

300  .6        .6 

29 


Table  No.  30  shows  our  new  required  silicon  must  be 
2.4  per  cent,  which  means  we  are  take  enough  of  the  pig 
iron  and  scrap  to  give  us  that  amount  and,  according  to 
table  31  we  must  use  50  per  cent  of  each.  As 'we  only 
require  1500,  that  means  we  are  to  take  750  pounds  of 
each  A  and  C,  together  with  the  500  pounds  of  steel  and 
no  more  figuring  is  required, — except  of  course  for  the  man- 
ganese. Example :  — 

As  we  have  25  per  cent  steel,  the  other  75  per  cent 
must  be  divided  between  A  and  C. 

Steel  25%  of  0.0%  silicon  equals     0.0     %  silicon 

Pig  37.5%  of  3.0%   silicon  equals      1.125%   silicon 

Scrap  37.5%  of   1.8%   silicon  equals     0.675%  silicon 


1.800%  silicon 
TABLE  No.  32. 

Table  32  shows  our  figures  are  correct  and  is  a  much 
shorter  method  than  table  27.  We  will  now  figure  the  man- 
ganese. Taking  the  same  percentage  as  in  table  32  we  will 
see  how  much  manganese  the  irons  figured  have  already 
brought  into  the  mixture.  Example:  — 
Steel  25%  of  0.5%  equals  0.125  %  manganese 

Pig  37.5%  of  0.5%   equals         0.1875%  manganese 

Scrap  37.5%  of  0.4%   equals          0.150   %   manganese 

0.4625% 
TABLE  No.  33. 

Table  33  shows  our  mixture  already  has  0.4625  per  cent 
manganese.  As  we  desire  0.85  per  cent  we  must  get  the 
other  0.3875  per  cent  from  the  12  per  cent  manganese  steel 
scrap.  This  0.3875  per  cent  of  course  is  what  we  desire, 
and  must  be  put  down  under  B.  The  12  per  cent  man- 
ganese under  C,  and  figured  as  in  table  22.  Example:  — 

By  using  the  figure  3  in  table  34,  we  save  a  lot  of 
figures  and  it  does  not  affect  the  result. 

30 


A.  B.  C. 

0.  .3875  12 

12)38.7500(3.23% 
36 


27 
24 


35 
36 

TABLE  No.  34. 

Table  34  shows  we  are  to  take  3.23  per  cent  of  C. 
To  find  how  much  steel  scrap  we  are  to  use,  we  will  multiply 
the  full  charge  of  2000  pounds  by  3.23  per  cent,  which 
gives  us  64.6  pounds.  Multiplying  the  64.6  pounds  by  the 
per  cent  of  manganese  it  contains,  which  is  12, — gives  us 
the  exact  amount  of  manganese  this  64.6  pounds  adds, — 
which  is  7.752  pounds.  This  again  divided  by  20,  the 
number  of  100  pounds  in  the  mixture,  will  give  us  our 
required  per  cent  of  manganese.  Multiplying  the  12  by 
3.23  per  cent,  will  also  give  us  our  required  per  cent  of 
manganese.  Example:  — 

2000                        20)7.7520 
03.23  


64.6000  Ibs. 


.3876%  man. 


64.6  12 

.12  03.23 


7.7752  Ibs.  .3876% 

Manganese    from   mixture  0.4625 

Manganese    from    12%    steel     0.3876 

Total  manganese  equals     0.8501% 
31 


TABLE  No.  35 

Using  the  figure  3  in  table  34,  altered  the  result  bu 
slightly,  and  saved  a  lot  of  figures.  To  use  this  64.6  Ibs 
of  12  per  cent  manganese  steel,  we  would  take  out  tha 
amount  from  the  500  pounds  of  the  common  steel  scrap. 


METHOD  OF  FIGURING  THREE  OR  MORE  ELEMENTS 
EXACT  IN  THE  SAME  MIXTURE 

We  have  shown  in  previous  mixtures  how  to  get  the 
exact  percentage  of  both  silicon  and  manganese  in  the  same 
mixture.  The  silicon  is  figured  correct,  and  the  manganese 
is  corrected  by  the  use  of  ferro-manganese.  But  now,  sup- 
pose we  have  to  get  another  element  exact, — say  phosphorus 
— to  specification? 

The  best  way  to  do  it  is  to  make  two  mixtures,  both 
to  contain  the  same  per  cent  of  silicon  we  desire  in  the  final 
mixture,  but  one  mixture  to  contain  a  lower  and  the  other 
to  contain  a  higher  per  cent  of  phosphorus  than  we  desire  in 
our  final  mixture.  We  then  take  the  phosphorus  contained 
in  each  of  these  two  mixtures  to  figure  the  exact  percentage 
of  phosphorus  we  desire  in  our  final  mixture.  So  you  see, 
when  we  have  two  mixtures,  each  containing  the  same  per 
cent  of  silicon,  no  matter  how  much  we  use  of  each  one 
to  get  our  desired  per  cent  of  phosphorus  in  the  final  mix- 
ture, the  silicon  will  not  be  changed.  Example: — 

We  wish  to  make  a  mixture  of  2000  pounds  to  contain 
2.3  per  cent  silicon,  0.65  per  cent  phosphorus,  and  0.75  per 
cent  manganese.  As  we  lose  from  0.10  to  0.15  per  cent 
in  melting,  we  will  make  our  mixture  to  contain  0.9  per 
cent  manganese. 

Silicon  Phosphorus  Sulphur  Manganese 

2.00%  0.4%  0.04%  0.60% 

3.00%  0.7%  0.02%  0.75% 

2.25%  0.6%  0.03%  0.65% 

2.75%  0.9%  0.01%  1.00% 

32 


TABLE  No.  37. 

When  mixing  for  Phosphorus  no  allowance  is  made  for 
gain  or  loss  in  melting.  Far  silicon  we  will  add  the  0.2  per 
cent,  making  our  desired  silicon  for  the  mixture  2.5  per  cent. 

We  will  make  our  first  mixture  from  the  first  two  irons, 
and  our  second  mixture  from  the  next  two.  You  will  notice 
we  have  tried  to  select  two  irons  that  will  give  us  a  lower 
and  two  that  will  give  us  a  higher  per  cent  of  phosphorus 
than  we  want  in  our  final  mixture. 

Setting  the  first  two  irons  under  their  proper  heading 
they  stand  ready  to  be  figured. 

First    Mixture  Second    Mixture 

Silicon  Silicon 

A.  B.  C.  A.  B.  C. 

2.0  2.5  3.0  2.25         2.50         2.75 

2.0  2.5  2.25         2.50 


.5  .5  .25  .25 

TABLE  No.  38. 

In  both  of  these  mixtures  we  get  even  remainders,  which 
shows  we  are  to  take  50  per  cent  of  all  the  irons. 

In  our  first  mixture  we  get  the  lowest  phosphorus  0.55 
per  cent,  as  50  per  cent  of  0.4  per  cent  equals  0.20  per 
cent  and  50  per  cent  of  0.7  per  cent  equals  0.35  per  cent, 
adding  these  two  together  we  get  0.55  per  cent  phosphorus, 
which  is  lower  then  we  desire  in  the  final  mixture,  but  we 
get  our  desired  silicon  2.5  per  cent. 

In  the  second  mixture  taking  50  per  cent  of  0.6  per  cent 
phosphorus  equals  0.3  per  cent  and  50  per  cent  of  0.9  per 
cent  equals  0.45  per  cent.  Adding  these  together  we  get  0.75 
per  cent  phosphorus  which  is  higher  than  we  require  in  the 
final  mixture.  But,  we  also  have  the  same  silicon  (2.5  per 
cent)  in  both  mixtures.  Now  we  have  two  mixtures,  both 
containing  the  same  per  cent  silicon,  but  one  has  a  higher 
and  the  other  has  a  lower  per  cent  of  phosphorus  than  we 

33 


want  in  the  final  mixture.  So  we  will  take  these  two  per 
cents  of  phosphorus  with  our  desired  per  cent  and  set  them 
under  their  proper  heading  and  figure  as  in  table  No.  1. 
Example :  — 

A.  B.  C.  Phosphorus 

.55          .65          .75 
.55          .65 


.10 


.10 


TABLE  No.  39 

As  both  remainders  are  the  same  again,  it  shows  we 
are  to  take  50  per  cent  of  each  mixture,  which  will  give 
us  our  required  per  cent  of  phosphorus  and  the  required  per 
cent  of  silicon  in  the  final  mixture. 

As  we  are  to  take  50  per  cent  of  each  of  the  first  mix- 
tures,  and   each   mixture   contains   two   irons,   it  is   apparent 
that  we  are  to  take  25  per  cent  of  each  iron. 
25%    of  2.00%   silicon  equals 
25%    of  3.00%   silicon  equals 
25%    of  2.25%   silicon  equals 
25%    of  2.75%  silicon  equals 


Example : 
0.50  % 
0.75  % 
0.5625% 
0.6875% 


2.5000% 

Silicon  loss  in  melting  0.2       % 

Silicon  in  castings  2.3       % 

25%    of  0.4%   phosphorus  equals  0.100% 

25%    of  0.7%   phosphorus  equals  0.175% 

25%    of  0.6%   phosphorus  equals  0.150% 

25%    of  0.9%  phosphorus  equals  0.225% 

Total  phosphorus  0.650% 

25%     of  0.6  %   Manganese  equals  0.150   % 

25%     of  0.75%   Manganese  equals  0.1875% 

25%     of  0.65%  Manganese  equals  0.1625% 

25%     of   1.00%   Manganese  equals  0.25      % 

0.7500% 
34 


TABLE  No.  40 

Our  mixture  gives  us  0.75  per  cent  Manganese,  leaving 
0.15  per  cent  for  the  fero-manganese  to  bring  in.  As  this 
0.15  per  cent  is  what  we  require,  we  will  set  it  under  B. 
The  80  per  cent  ferro-manganese  under  C  and  figure  as  in 
tables  22,  23,  24  and  25. 

A.        B.        C. 
0        0.15      80 

Affix  two  ciphers  to  B,  move  the  decimal  point  two 
places  to  the  right  and  divide  by  .80.  Example:  — 

80)I5.0000(.1875%  of  C.  Ferro-Manganese. 
80 


700 
640 

600 
560 


400 
400 

2000  Ibs.  80 

.001875  .001875 


3.750000  Ibs.  Ferro-Mang.  .1 50000% 

TABLE  No.  41 

Our  figures  show  we  are  to  take  00.1875  per  cent  of 
C  ferro-manganese,  by  multiplying  the  80  per  cent  ferro- 
manganese,  by  the  00.1875  per  cent  will  give  us  our  required 
manganese.  And  by  multiplying  the  2000  Ib.  charge  by  the 
percentage  of  ferro-manganese  00.1875  we  are  to  use,  will 
give  us  the  amount  of  fero-manganese  in  pounds  we 
are  to  use. 

Manganese    from   mixture   equals  0.75% 

Manganese  from  ferro-man.  equals  0.15% 

O90~~ 

Loss  in  melting  0.15 


Total  manganese  equals  0.75% 

35 


FRENCH  SPECIFICATIONS  FOR  SHELLS  OF  122  TO  155 
MILLIMETERS  CALIBER  TO  BE  CAST  IN  SAND 


By  Edgar  Allen  Custer  in  "The  Foundry" 

Silicon         Phos.         Sulphur         Mang.       C.  Carb.      G.Carb. 
1.2%        0.15%        0.08%        0.70%        0.70%       2.40% 

The  above  analysis  are  for  dry  sand  molds,  if  cast  in 
green  sand,  the  silicon  should  be  about  1 .35  per  cent.  The 
total  carbon  and  silicon  must  not  exceed  4.7  per  cent.  If 
this  limit  is  exceeded,  the  iron  will  lack  toughness,  at  least 
20  per  cent  of  the  total  carbon  must  be  combined  to  produce 
proper  fragmentation.  The  percentage  of  dust  increases  as 
the  combined  carbon  decreases.  The  charge  should  be  as 
follows:  Pig  iron  40  per  cent,  scrap  40  per  cent  and 
steel  20  per  cent.  The  term  scrap  is  used  to  denote  scrap 
melted,  pigged  and  charged  according  to  analysis.  All  the 
foundries  in  France  engaged  in  this  work  have  been  mobi- 
lized on  a  common  basis,  and  are  using  precisely  the  same 
methods  of  selection,  analysis  and  general  foundry  procedure. 
This  has  not  been  done  without  enormous  losses  and  vex- 
atious delays.  There  have  been  many  cases  where  the 
loss  of  a  total  heat  has  been  reported,  and  the  loss  of  40 
per  cent  was  not  uncommon  in  the  first  stages.  Team  work, 
scientific  methods  and  keeping  everlastingly  at  it,  have 
brought  results.  Today,  September  1917,  the  output  has 
reached  staggering  proportions,  over  1 ,000,000  rounds  per 
day  are  being  made. 

This  must  certainly  be  interesting  to  every  metal  mixer, 
and  should  have  a  tendency  to  induce  him  to  try  his  hand 
at  making  mixtures  for  shells,  so  as  to  be  prepared,  to  some 
extent,  for  any  emergency. 

We  will  make  a  mixture  as  near  as  possible  to  the 
French  specifications,  from  some  Iron  Mountain  pig  iron 
which  I  recently  had  analyzed,  and  some  scrap  we  will 
presume  contains  the  following  analysis  after  it  has  been 
melted  and  pigged. 

36 


Sil.  Phos.  Sul.  Mang.  C.  C.  G.  C. 

Iron    Mountain             1.4%  0.14  0.011  1.22  0.60  2.70 

Selected    scrap            2.0  0.40  0.080  0.55  0.40  3.00 

Steel   scrap                   0.2  0.01  0.040  0.50  0.10 

TABLE  No.  42 

In  making  this  mixture  we  will  use  the  silicon  in  the 
steel,  although  as  a  rule  I  leave  it  out  when  making  a 
mixture  to  contain  a  certain  percentage  of  steel.  According 
to  the  specifications  our  mixture  must  contain  1 .2  per  cent 
silicon,  adding  0.2  per  cent  for  loss  in  melting,  will  make 
our  desired  silicon  1 .4  per  cent.  As  we  are  to  use  20  per 
cent  steel,  we  will  get  0.04  per  cent  from  it,  leaving  1 .36 
per  cent  for  the  pig  iron  and  scrap  to  bring  into  the  mixture. 
Now,  as  we  only  want  80  per  cent  more  iron,  and  this  80 
per  cent  will  have  to  carry  enough  silicon  to  give  us  1 .36 
per  cent  for  the  whole  mixture  of  2000  pounds,  that  means 
we  are  to  find  a  new  temporary  per  cent  of  silicon  to  work 
with.  So  by  using  the  same  rule  as  in  table  30 — that  is  by 
dividing  the  actual  per  cent  of  silicon  desired  by  the  per- 
centage of  iron  used  in  the  mixture,  which  in  this  case  is 
80  per  cent,  we  get  the  new  per  cent  of  silicon,  1 .7  to 
work  with, — see  the  point.  We  must  get  1 .7  per  cent 
silicon  in  80  per  cent  of  the  mixture  to  give  us  1 .36  per 
cent  more  silicon  to  the  whole  mixture.  Example:  — 

TABLE  No.  43.  TABLE  No.  44 

.80)1.360(1.7%   silicon.  A.        B.        C. 

80  1.4       1.7       2.0 

1.4       1.7 


560 


560  3         .3 

The  result  of  table  44  shows  we  are  to  use  the  same 
percentage  of  each  pig  iron  and  scrap,  which  in  this  case 
is  40  per  cent,  with  20  per  cent  of  steel.  So  figuring  all 
the  elements  on  that  basis,  we  will  see  how  near  our  mix- 
ture is  to  the  specifications.  Example:  — 

37 


Iron  Mountain 
Selected  scrap 
Steel  scrap 


40%  of  1.4%  silicon  equals 
40%  of  2.0%  silicon  equals 
20%  of  0.2%  silicon  equals 


Loss  in  melting 
Silicon    in   mixture 
Phosphorus. 


0.560% 
0.800% 
0.040% 

1.400% 
0.2  % 

1.2    % 


Iron  Mountain  40%  of  0.14%  phosphorus  equals  0.056% 
Selected  scrap  40%  of  0.40%  phosphorus  equals  0.160% 
Steel  scrap  20%  of  0.01%  phosphorus  equals  0.002% 

Phosphorus   in   mixture  0.218% 

Sulphur. 

Iron  Mountain  40%  of  0.011%  sulphur  equals  0.0044% 
Selected  scrap  40%  of  0.080%  sulphur  equals  0.0320% 
Steel  scrap  20%  of  0.040%  sulphur  equals  0.0080% 


Gain  in  melting 


Sulphur  in  mixture 
Manganese. 

Iron  Mountain  40%  of  1.22%  manganese  equals  0.488% 
Selected  scrap  40%  of  0.55%  manganese  equals  0.220% 
Steel  scrap  20%  of  0.50%  manganese  equals  0.100% 


Loss  in  Melting 
Manganese  in  mixture 
38 


Combined  Carbon 

Iron    Mountain          40%  of  0.6%  C.  C.  equals  0.240% 

Selected  scrap  40%  of  0.4%  C.  C.  equals  0.160% 

Steel  scrap  20%  of  0.1%  C.  C.  equals  0.020% 


0.420%, 
Graphite  Carbon 

Iron    Mountain  40%  of  2.7%  G.  C.  equals      1 .08% 

Selected  scrap  40%  of  3.0%  G.  C.  equals      1 .20% 

Steel   scrap  20%  of  0.0%  G.  C.  equals     0.00% 

2.28% 
TABLE  No.  45. 

These  tables  show  that  all  the  elements  are  very  nearly 
what  the  specifications  call  for.  Even  though  phosphorus  is 
a  little  higher  here,  there  is  not  the  least  doubt  it  would  be 
lower  in  actual  practice,  even  from  this  mixture.  If  is  was 
not,  we  would  use  two  grades  of  pig  iron,  and  melt  and 
pig  two  different  grades  of  scrap,  and  get  our  phosphorus 
exact,  by  the  same  method  as  in  table  38  and  39.  The 
carbons  we  cannot  tell  very  much  about  till  after  analysis 
has  been  made  from  the  mixture,  because  it  is  a  semi-steel 
mixture.  But  both  carbons  will  be  well  within  specifications, 
which  says  the  combined  should  be  at  least  20  per  cent 
of  the  total  carbon.  As  this  mixture  shows  over  15  per 
cent,  it  is  bound  to  be  higher  in  the  casting  on  account 
of  the  low  silicon,  and  high  steel  in  the  mixture.  Successful 
mixtures  of  this  kind  are  not  accomplished  with  one  trial. 
And  like  the  French  foundrymen,  only  sticking  everlastingly 
at  it,  would  we  accomplish  the  desired  results. 


39 


SIDE  LIGHTS  ON  MIXTURES 

In  making  some  mixtures  you  will  find  when  dividing 
your  first  remainder,  that  to  get  the  exact  result,  you  would 
be  compelled  to  carry  it  out  to  several  decimal  places.  Now, 
if  it  will  not  finish  with  one  decimal  place,  just  raise  the 
last  decimal  or  figure  in  the  quotient,  one  more.  Although 
the  divisor  will  not  go  that  many  times,  still  it  will  save 
a  lot  of  figures,  and  will  not  affect  the  result  any.  But, 
be  sure  and  do  this  with  the  first  remainder  only,  then  you 
will  always  have  the  full  percentage  of  the  element  you  are 
figuring  for;  Example:  — 

Suppose  we  wish  a  mixture  of  1500  pounds  to  contain 
2.2  per  cent  silicon.  We  will  make  it  from  1 .8  per  cent 
silicon  scrap,  and  50  per  cent  ferro-silicon. 

TABLE  No.  46 

A.  B.  C. 

1.8  2.2  50.0 

1.8  2.2 


.4          47.8 
47.8 


48.2)40.000(  .83%  of  C  iron 
3856    99. 17%  of  A  iron 


1440 
1446 

As  there  are  two  more  decimal  places  in  the  dividend 
than  in  the  divisor,  we  point  off  two  decimal  places  in  the 
quotient  making  it  .851  jhtindredths  per  cent  of  C  iron  to  be 
used,  and  99.17  per  cent  of  A  iron  to  be  used. 
A  iron  1.8%  silicon         C  iron  50%  silicon 

Take  99. 1  7%  of  A  iron      Take  .0083%  of  C  iron 


silicon  4,50%  si]icon 

.4150 

2.20006%  silicon 

^40 


You  will  notice,  by  using  the  figure  3  in  table  46  did 

not  make  any  material  difference  to  the  result.     But  saved 

carrying  the  quotient  to   several   decimal  places. 

We  will  try  another  from  3.25  per  cent  pig  iron,  instead 
of  ferro-silicon. 

A.  B.  C. 

1.8  2.2  3.25 

1.8  2.2 


.4  1.05 

1.05 


1.45)40.00(28%  of  C  iron. 
290       72%  of  A  iron. 


1100 
1160 


TABLE  No.  47. 

A  iron  1.8%  silicon          C    iron  3.25%  silicon 

Take  72%  of  A  iron      Take  28%  of  C  iron 


1.296  .9100 

1.296 


2.2060%  silicon 

Even  by  having  too  much  by  60  in  table  47  only  added 
6  thousandths  of  one  per  cent  to  the  silicon,  but  saved  quite 
a  lot  of  figures. 

By  taking  advantage  of  this  idea  when  you  are  dividing 
your  first  remainder,  if  the  figures  are  inclined  to  run  to 
several  decimal  places,  you  will  always  get  the  full  percent- 
age of  silicon,  or  any  other  element  you  may  be  figuring 
for.  Table  46  says  we  are  to  take.  .83  hundredths  of  one 
per  cent  of  the  C  iron  and  99.17  per  cent  of  A  iron. 

41 


Example:  — 
Charge        1500  pounds 

00.83%     of  C  iron 


1 500   pounds 
99.17%    of  A  iron 


4500 
12000 


1487.5500  Ibs.  of  A  iron 
12.4500 


12.4500  Ibs.  of  C  iron 


1500.0000  pounds 


Table  47  says  we  are  to  take  28  per  cent  of  C  iron  and 
72  per  cent  of  A  iron.     Example:  — 


Charge 


1500  pounds 
.28%  of  C  iron 


12000 
3000 

420.00  Ibs.  C  of  iron 


1500   pounds 
.72%    of  A  iron 


3000 
10500 

1080.00  Ibs.  A  iron 
420.00 


1500.00  pounds. 


42 


MISCELLANEOUS  MIXTURES 


These  mixtures  are  taken  from  my  note  books  and  was 
cast  several  years  ago  from  the  following  irons.  The  cast- 
ings answered  their  purpose  and  finished  up  clean.  You 
will  notice  the  steel  mixtures  are  made  from  irons  low  in 
sulphur  and  phosphorus  with  manganese  from  0.75  per 
cent  up. 

Piston  Valve  Liners 

70%  Carron  No.  1  ;  Tranverse  2800  per  sq.  inch. 
30%  steel  scrap ;  Silicon  1 .6  per  cent  in  casting. 

Hammer  Block 

60%   Foundry  scrap;    Tranverse  3600. 
40%  Steel  scrap;  Silicon  1.16  per  cent. 

Stamp   Heads 

68%   Shop  scrap;   Tranverse  3900. 
32%   Steel  scrap;    Silicon   1.09  per  cent. 

V  Gear  8'  6"  Dia.  9"  Face,  Hub  Split. 
74%  cyl.  Niagara;  Silicon  1.2  per  cent. 
26%  Steel  scrap. 

Large  Marine  Cylinder.  Net  Weight  34,020  Ibs. 
30%  Gun  iron;   Silicon    1.7  per  cent  in  casting. 
30%   Cyl.  Niagara. 
30%  Shop  scrap. 
10%  Carron  No.   1. 

McCully  Crusher  No.  7 

85%  Texada  No.  2;   Test  piece  Chilled  2%  deep. 
15%   Steel  scrap;   Silicon  0.85  per  cent. 

90-inch  Snap  and  Bull  Rings 

67%  Carron  No.   1  ;   Silicon   1 .6  per  cent  in  casting. 
33%  Steel  scrap. 

43 


Two  Marine  Cyl-Liners,  6927  and  7134  Ibs.  Net 

56.25%   Gun   iron;    Silicon   estimated   1.2%. 

25.00%   Carrqn;    1st  liner  cast    1.07%. 

18.75%   Steel  scrap;    2nd  liner  cast  0.97%   silicon.  * 


16.000  pounds. 

Good  For  Strong  Castings  and  Semi-Steel 

Brand—  Sil.    Phos.     Sul.    Mang.  C.C.     F.C.     G.C. 

Carron  2.8     0.50     0.035  1.45      3.64      

Texada  No.  2  1 .25  0.30    0.025  0.90     

Cyl.  Niagara  1.80  0.50     0.044  0.75      

Car  Wheels  0.70  0.40     0.16  0.50       0.9      2.90 

Gun   iron  1.25  0.31      0.070  0.60      

Iron    Mountain  1.400.14     0.011  1.22       0.6      2.70 

Irondale  2.300.16     0.035  1.10      

Niagara  No.  2  2.20  0.40    0.04  0.60     3.58     

Muirkirk  2.21  0.28    0.031  2.22    0.55     3.01 

Good  for  Soft  Iron  Work 

Sloss  No.   1         3.60  0.65    0.03      0.45 

Crown  No.  1        3.25  0.71     0.022    0.50     

Clifton  No.  1        3.500.50    0.015     1.40      0.3     3.30 

Mississippi  3.34  0.294  0.022    0.90     

Grading  numbers  will  correspond  closely  to  the  follow- 
ing percentages  of  silicon  and  sulphur. 

No.  1  Pig  No.  2.  No.  3.  No.  4. 

Silicon     2.75  to  3.50%  2.25  to  2.75  2.00  to  2.25  1 .75  to  2.00 
Sulphur   0.02  to  0.04%  0.01  to  0.03  0.01  to  0.03  0.01  to  0.03 

No.  5.  No.  6.  No.  7.  No.  8. 

Silicon     1 .50  to  1 .75%  1 .25  to  1 .50  1 .00  to  1 .25  0.75  to  1 .00 
Sulphur   0.02  to  0.04%  0.02  to  0.04  0.03  to  0.04  0.03  to  0.05 

The  following  analysis  of  a  few  of  the  most  important 
castings,  will  give  the  young  student  some  idea  to  work  on 
while  making  mixtures. 

44 


If  from  five  to  ten  per  cent  of  steel  is  mixed  in  these 
mixtures,  it  will  strengthen  and  improve  the  castings  for 
this  class  of  work. 

Silicon  Phos. 

Hydraulic   Cylinders  .5  .40 

Amonia  Cylinders  .6  .60 

Air   Cylinders  .3  .45 

Steam  Cylinders,  Heavy  .6  .40 

Steam  Cylinders,   Small  .9  .55 

Gas    Engine    Cylinders  .8  .50 

Locomotive    Cylinders  .6  .55 

Automobile  Cylinders  2.2  .50 

Propeller   Wheels  .4  .30 

Bed  Plates,  Heavy  .9  .55 

Dynamo   Frames  2.5  .80 

Approximate  rule  for  weighing  pig  iron  in  piles : 
If  piled  in  the  usual  way  7^4  cubic  feet  will  weigh  one 
ton.     If  very  closely  piled  7  cubic  feet  will  weigh  one  ton. 


Sulp. 

Mang. 

.08 

.8 

.09 

.7 

.09 

.8 

.09 

.8 

.08 

.6 

.07 

.7 

.08 

.6 

.08 

.7 

.09 

.8 

.08 

.6 

.07 

.5 

45 


THE  INFLUENCE  DIFFERENT  ELEMENTS  HAVE 
UPON  THE  IRON. 


Silicon. 

Silicon  will  soften  the  iron  up  to  3.50  per  cent.  When 
iron  contains  more  it  begins  to  get  hard,  short  and  brittle. 
Silicon  increases  fluidity,  decreases  shrinkage,  open  the  grain 
of  the  iron  and  helps  to  turn  combined  carbon  into  graphite 
carbon,  which  helps  to  reduce  the  strength  of  the  iron.  In 
melting  we  lose  about  0.2  per  cent  of  silicon,  which  amount 
must  be  taken  into  account  when  figuring  for  silicon. 

Phosphorus. 

Phosphorus  helps  to  make  iron  fluid  and  weak,  so  for 
all  kinds  of  castings  except  the  very  thinnest,  it  should  not 
be  over  0.7  per  cent.  But  for  light,  thin  castings  where 
strength  is  of  no  importance,  it  can  run  as  high  as  1.0  or 
1.25  per  cent.  In  fact  iron  for  stove  plate  and  that  line 
of  work  require  that  much.  Phosphorous  lowers  the  melting 
point  of  iron,  and  decreases  the  shrinkage.  In  melting  it 
neither  loses  or  gains  very  much.  So  no  provision  for  loss 
or  gain  is  required  when  making  mixtures. 

Sulphur 

Sulphur  if  too  high  will  make  the  iron  hard.  Increase 
the  shrinkage  and  promote  chill,  and  cause  the  iron  to  con- 
geal quickly.  If  very  high  it  will  cause  blow  holes,  shrinkage 
cracks  and  dirty  iron.  In  all  machinery  castings  it  should 
be  kept  below  0.9  per  cent  if  possible.  In  melting  it  gains 
about  0.03  to  0.035  per  cent,  chiefly  from  the  fuel.  This  gain 
must  be  taken  into  account  when  making  mixtures. 

Manganese. 

Manganese  is  one  of  the  best  elements  we  have  in  iron. 
It  is  a  regular  scavenger.  There  is  no  element  that  will 
cleanse  the  iron,  reduce  the  blow  holes,  reduce  the  sulphur, 

46 


increase  the  strength  and  improve  the  grain  like  manganese. 
When  silicon  is  normal  for  the  work  being  made,  manganese 
from  0.5  to  0.8  per  cent  will  be  alright.  In  melting  we  lose 
from  0.10  to  0.15  per  cent. 

Graphite  Carbon. 

Graphite  carbon  is  a  softener.  It  opens  the  grain  of 
the  iron,  makes  it  soft,  weaker  and  reduces  shrinkage  and 
chill. 

Combined  Carbon 

Combined  carbon  is  a  hardener.  It  closes  the  grain  of 
the  iron,  increases  the  strength,  shrinkage  and  chill.  In  melt- 
ing there  is  no  gain  or  loss,  only  that  one  form  will  change 
to  the  other  according  to  the  rate  of  cooling,  and  influence 
of  the  other  elements,  especially  silicon  and  manganese.  In 
the  common,  soft  foundry  pig  irons,  combined  carbon  will  run 
about  0.30  per  cent  to  0.50  per  cent.  Graphite  carbon  will 
run  about  3.0  per  cent  to  3.5  per  cent.  But  as  the  iron  is 
made  harder  by  mixing,  the  carbons  will  change,  Graphite 
carbon  getting  lower  in  per  cent  and  combined  carbon  in- 
creasing in  percentage,  according,  of  course,  to  the  per  cent 
of  silicon  put  into  the  mixture.  Graphite  carbon  will  be 
high,  when  silicon  is  high,  and  combined  carbon  will  increase 
as  silicon  is  lowered. 

Approximate  per  cent  of  Silicon  for  Different  Castings 

I  have  found  castings  containing  the  following  percent- 
ages of  silicon,  were  satisfactory,  both  in  machining  and  use. 

For  light  castings  from  %  to  one-inch  in  section.  From 
2.25  to  1 .9  per  cent  silicon.  Castings  from  1  inch 
to  2  inches  in  section.  From  1 .9  to  1 .6  per 
cent  silicon.  Castings  from  2  inches  to  3  inches  in 
section,  from  1 .6  to  1 .3  per  cent  silicon.  These  figures  are 
given  to  give  the  reader  an  idea  how  to  regulate  the  silicon 
for  castings  of  different  section,  and  if  the  other  elements 
are  kept  normal  by  selecting  irons  suitable  for  the  class  of 
work  being  made,  will  be  entirely  satisfactory  for  all  kinds 

47 


of  general  machinery  castings  when  figuring  for  silicon  only. 
For  pulleys  the  silicon  should  range  from  2.3  per  cent  to  2.6 
per  cent,  and  the  sulphur  should  be  kept  below  0.06  per 
cent  if  possible.  For  large  Marine  cylinders  with  brackets 
and  flanges  liable  to  crack  through  unequal  sections,  the 
silicon  should  run  from  1 .6  per  cent  to  1 .8  per  cent.  The 
castings  of  course,  always  have  liners  of  much  harder  metal. 
Small  and  medium  sized  cylinders  with  no  liners  should  run 
from  2.0  to  1.6  per  cent  silicon,  with  10  to  15  per  cent  steel. 
For  large  gear  wheels,  blank  or  otherwise  should  contain, — 
after  20  to  25  per  cent  steel  has  been  added, — about  1 .6 
per  cent  silicon.  Car  wheels,  from  10-inch  mining  wheels, 
up  to  regular  passenger  car  wheels,  from  1.5  to  0.70  per 
cent  silicon.  From  5  to  10  per  cent  steel  scrap  always  helps 
the  chill  and  strength  of  the  wheels.  All  car  wheels  should 
be  annealed  as  soon  as  possible  after  casting,  by  putting  into 
a  pit  altogether. 

When  selecting  pig  iron  for  small  and  medium  castings, 
try  and  get  iron  containing  less  than  0.03  per  cent  sulphur, 
phosphorus  about  0.7  per  cent,  Manganese  about  0.6  per 
cent  or  0.8  per  cent,  with  graphite  carbon  about  3.25  per  cent 
and  combined  carbon  0.25  per  cent  or  under.  In  the  castings 
the  sulphur  will  average  about  0.08  per  cent.  The  other  ele- 
ments will  not  vary  very  much.  In  the  heavier  castings  the 
sulphur  should  not  exceed  0.095%,  phosphorus  should  be 
kept  down  from  0.4  to  0.5%,  manganese  about  0.8  to  0.9 
per  cent.  Graphite  carbon  will  run  from  2.50  per  cent  to 
2.75  and  combined  about  0.75  per  cent. 

Judging  the  percentage  of  silicon  in  Different  Kinds  of  Scrap. 

As  a  general  rule  light  machinery  scrap  will  contain 
about  1.9  per  cent  to  2.25  per  cent  silicon.  But  sometimes 
we  run  across  heavy  scrap  that  runs  that  high  in  silicon.  In 
that  case,  as  a  rule,  the  fracture  will  show  a  dark  rough  sur- 
face, full  of  shining  particles  of  graphite,  whereas  the  low 
silicon  heavy  scrap,  will  show  a  lightish,  slightly  rough  frac- 
ture. 

48 


Heavy  scrap  from  1J/2  inches  to  3  inches  in  section,  will 
run  from  1 .8  per  cent  to  1 .25  per  cent  silicon. 

Standard  car  wheels — silicon  0.7  per  cent,  phosphorus 
net  over  0.4  per  cent,  manganese  0.4  to  0.5  per  cent,  sulphur 
not  over  0.17  per  cent,  graphite  carbon  from  2.5  to  2.9  per 
cent,  combined  carbon  not  over  0.90  per  cent. 

Steel  plate  scrap  contains  silicon  about  0.2  per  cent, 
phosphorus  from  0.01  to  0.05  per  cent,  sulphur  form  0.03 
to  0.05  per  cent,  and  manganese  0.5  per  cent,  with  total 
carbon  about  0.10  per  cent. 

Stove  plate  scrap  runs  about  2.75  per  cent  silicon,  phos- 
phorus about  1 .0  per  cent.  Although  stove  plate  scrap  is 
high  in  silicon,  it  is  a  quantity  that  cannot  be  depended 
upon,  on  account  of  its  thin  section,  both  the  iron  and  the 
elements  in  it  are  burnt  somewhat,  especially  so  if  melted 
under  high  blast.  Use  it  with  judgment.  If  light  and 
heavy  scrap  are  brought  together,  it  will  pay  to  sort,  and 
give  each  its  proper  rating,  which  with  a  little  experience 
can  soon  be  learned. 

DECIMAL  FRACTIONS 

In  adding  a  few  examples  on  decimal  fractions  and 
percentage,  I  thought  would  be  an  advantage  to  those  who 
have  allowed  themselves  to  get  rusty  on  decimals — to  have 
under  the  same  cover, — as  a  ready  reference  while  working 
over  the  mixtures. 

Addition  of  Decimals 

The  only  respect  in  which  addition  of  decimals  differ 
from  simple  addition  is,  in  placing  the  decimal  point  directly 
over  one  another.  Example:  — 

26.346 
.263 


26.609 

49 


Substraction  of  Decimals 

Substract  as   in   whole   numbers,   but   keep   the   decimal 
points  directly  under  each  other,  as  in  addition.  Example:  — 
80.312 
79.200 


1.112 

Multiplication  of  Decimals 

Multiply    as    in    whole    numbers,    and    point    off    in    the 
product  as  many  decimal  places  as  there  are  decimal  places 
in   the   two   factors,   and   if   the   product   has1  not   so   many, 
supply  the  defect  by  writing  ciphers  on  the  left  hand. 
Example :  — 

1st—  2nd— 

.33  32.3 

.2  2.3 


.066  969 

646 


74.29 

Note:  In  the  first  example  there  are  three  decimal 
places,  so  must  make  three  decimal  places  in  the  product 
by  adding  one  cipher  to  the  left  hand  of  it. 

Division  of  Decimals 

Divide  as  in  simple  numbers  and  point  off  as  many 
decimal  places  in  the  quotient,  as  the  number  of  decimal 
places  in  the  dividend  exceeds  the  number  in  the  divisor. 
If  necessary  prefix  ciphers  to  the  quotient;  or  affix  ciphers 
to  the  dividend.  When  both  dividend  and  divisor  contam 
the  same  number  of  decimal  places,  the  quotient  is  a  whole 
number,  without  or  with  a  remainder  as  the  case  may  be. 

50 


Example:  — 

No.  1     Divide  60  by  1.5. 

No.  2.    Divide  34.75  by  2.5. 

Divisor  Dividend  Quotient 

1.5  )         60.0         (        40 

600 

2.5)34.75(13.9 
25 


97 
75 


225 
225 

In  the  first  example  the  divisor  has  one  decimal  place, 
but   the  dividend   has   none,   so   one   must  be   affixed  to  it. 
As  the  dividend  must  have  as  many,  if  not  more,  decimal 
places  as  the  divisor,  with  the  added  decimal  place  in  the 
dividend    makes    the    quotient    a    whole    number.        In    the 
other  example  the  dividend  has  one  decimal  place  more  than 
the  divisor,  so  we  point  off  one  in  the  quotient. 
Example  No.  3.     Divide  30.5  by  .9. 
Example  No.  4.     Divide  70  by   11.2. 

.9)30.5  (33-8/9      1 1 .2)  70.000(6.25 
27  672 


35  ,  280 

27  224 


8  560 

560 

In  the  3rd  example  we  find  we  could  not  bring  it  to 
an  end,  so  to  save  carrying  it  on  to  several  decimal  places, 
we  have  finished  with  a  vulgar  fraction,  and  as  the  dividend 
has  the  same  number  of  decimal  places  as  the  devisor,  the 
quotient  is  a  whole  number,  with  the  fraction  8/9. 

In  the  4th  example  we  had  to  add  three  more  ciphers- 

51 


to  the  dividend,  giving  it  two  more  decimal  places  than  the 
divisor,  so  we  point  off  two  decimal  places  in  the  quotient. 

Percentage 

Percentage  is  the  process  of  calculating  by  the  hun- 
dreths.  Thus  5  per  cent  of  a  quantity  is  5  of  every  hun- 
dred, or  5  hundredths  of  the  quantity.  When  multiplying 
for  a  percentage  of  a  certain  number,  the  multiplier  is  ex- 
pressed decimally.  That  is,  if  we  are  to  take  5%,  25%  and 
12j/2%  of  a  number,  we  would  set  them  down  to  multiply 
like  this:  .05.25  and  .125.  The  following  table  will  show 
our  meaning: 

PER  CENT  DECIMAL  PER  CENT  DECIMAL  PER  CENT  DECIMAL 


1% 

2% 

3.1% 

10% 

50% 


.01 
.02 
.031 
.10 
.50 

75% 
100% 
150% 
500% 

.75 
1.00 
1.50 
5.00 
.0025 

1!/2% 
8/3% 
12/2% 

.005 

.0075 

.015 

.08J/3 

.125 


In  the  first  place  the  base  is  the  number  on  which  the 
percentage   is  computed. 

Example: — Suppose   we  wish  to  take  6J/4   per  cent  of 
12.7  per  cent.     The  12.7  is  the  base,  and  the  6J/4  is  the  rate, 
so  multiplying  the  base  by  the  rate  decimally  expressed  we 
get  the  percentage  of  .79375. 
Example:  — 

12.7 
.0625 


635 
254 
762 

.79375% 

As  explained  in  the  multiplication  of  decimals,  we  must 
point  off  as  many  places  in  the  product  as  there  are  in  the 
multiplier,  and  the  multiplicand  which  is  five.  It  will  be 
noticed  that  although  we  called  12.7  a  per  cent,  it  became 

52 


a   base    as   soon    as   we  wished   to   take    a   percentage    from 
it.     Examples. 

2.  Take  50%  of  2.75%. 

3.  Take  30%   of  3.25%. 

4.  Take  70%  of   1.75%. 

2.75  3.25  1.75        Base. 

50  .30  .70        Rate 


1.3750%  .9750%  1.2250%    Percentage 

When   two   numbers   are   given    and   we   wish   to    know 

the  rate  of  each  one,  we  add  the  two  together,  and  divide 

each    number,— after   affixing    two    ciphers    and   moving    the 

points   two    places    to    the    right,   by    the    sum    of    the    two. 

Example :  — 

What  per  cent  of  1.50  is  .45  and  1.05? 

.45 
1.05 


1.50)45.00(30% 

4500 
1.50)105.00(70% 

10500 

When  multiplying  for  percentage  with  decimals,  we 
must  always  point  off  two  extra  in  the  result  for  the  whole 
numbers.  Example:  Suppose  we  wish  to  take  .5625  per 
cent  of  80  per  cent  80 

.005625 


You  notice  we  have  added  two  .450000 
ciphers,  which  represent  the  two  whole  numbers,  and 
of  course  moves  the  decimal  point  two  places  to  the  left, 
so  in  pointing  off  the  result,  we  count  six  decimal  places.  Of 
course  in  actual  practice,  we  imagine  the  two  whole  numbers 
are  there,  and  point  off  the  result  accordingly. 

Hoping  these   few  suggestions  will   carry  the  point,   we 
will  not  go  any  deeper  on  this  subject. 

53 


CUPOLA   PRACTICE 


Although  it  is  not  the  purpose  of  this  book  to  treat  on 
cupola  practice,  I  feel  I  could  not  conclude  it  without  a 
word  or  two.  We  may  make  our  mixtures  as  they  should  be 
made,  still  there  is  a  possibility  of  them  going  wrong  by  im- 
proper handling  and  charging  of  the  cupola. 

If  every  melter  would  take  the  trouble  to  find  the 
proper  height  the  coke  bed  should  be  for  his  particular 
cupola,  then  make  all  his  charges  of  iron  from  first  to  last 
as  near  the  same  weight  as  possible,  he  will  get  a  more  uni- 
form grade  and  even  flow  of  iron,  with  less  coke  consumption, 
than  the  man  who  crowds  his  coke  bed  to  the  limit  with  an 
extra  heavy  first  charge  of  iron.  The  proper  practice  calls 
for  the  same  weight  of  charge  on  the  bed  as  every  succeed- 
ing charge,  and  the  weight  of  that  charge  is  figured  by  the 
weight  of  coke  it  takes  to  fill  four  inches  high  in  the  cupola. 
Then  use  a  ten  to  one  ratio,  that  is  if  it  takes  150  pounds  of 
coke  to  fill  four  inches  high  in  the  cupola,  the  iron  charges 
should  be  about  1500  pounds  and  so  on. 

Experimenting  foundry  men  have  proved  the  melting 
zone  averages  from  four  to  five  inches  in  depth.  And  they 
have  also  found  that  amount  of  fairly  good  coke  will  melt 
10  times  its  weight  in  iron  and  when  that  amount  of  iron 
is  melted,  the  bed  is  then  ready  for  another  four  inch  layer 
of  coke.  Now,  when  I  speak  of  a  four  inch  layer  of  coke, 
I  do  not  mean  that  we  must  put  four  inches  all  over  the 
inside  area  of  the  cupola.  That  rule  is  only  used  as  a  stan- 
dard on  which  to  figure  our  iron  charges.  It  has  been 
proved  that  the  best  results  have  been  derived  by  putting 
all  the  coke  in  the  center,  and  all  the  iron  as  close  to  the 
lining  as  possible,  excepting  of  course,  when  making  different 
mixtures  which  must  be  separated  by  coke.  By  this  method 
of  charging,  the  coke  can  be  reduced  and  still  have  hot  iron 
if  the  bed  and  first  charge  have  been  started  right.  When 

54 


the  bed  is  the  right  height  it  is  only  the  top  four  inches 
that  does  the  real  melting,  so  if  the  bed  is  higher  than  it 
should  be  the  extra  coke  will  be  burnt  and  wasted  until 
it  lets  the  iron  down  to  the  real  melting  zone,  which  will 
vary  from  15  to  28  inches  above  the  tuyers  according  to 
high  or  low  blast,  so  the  main  point  is  to  find  the  proper 
height  of  the  bed  for  every  cupola,  and  the  best  way  to  find 
it  is  by  the  time  it  takes  the  iron  to  drop  lively  after  the 
blast  is  on.  If  it  takes  more  than  three  minutes  at  the  most 
the  bed  is  too  high,  and  the  extra  time  will  be  taken  up 
burning  coke  that  is  not  required.  Now  then,  it  is  generally 
upon  high  coke  beds  that  extra  heavy  first  charges  of  iron 
are  put,  because  we  are  under  the  impression  that  so  much 
coke  on  the  bed  ought  to  melt  a  much  heavier  charge  than 
the  rest  of  the  charges.  But  it  is  a  wrong  impression.  An- 
other reason  for  heavy  first  charges  are,  that  most  foundries 
have  some  special  mixtures  to  make,  different  from  their 
regular  run  of  work,  and  if  they  happen  to  be  heavier  than 
their  regular  charges,  the  bed  is  considered  the  best  place, 
so  as  to  get  them  down,  and  out  of  the  way  of  the  regular 
mixtures.  But,  as  we  must  put  an  heavier  split  of  coke  between 
two  different  mixtures,  the  bed  is  built  up  somewhat,  the 
amount  it  has  lost  by  having  an  extra  heavy  first  charge 
to  melt,  and  I  believe,  that  one  reason  of  having  to  put 
an  heavier  split  of  coke  between  two  different  mixtures,  have 
saved  many  a  coke  bed  from  getting  dangerously  low  with- 
out the  melter  being  aware  of  it.  Now  here's  the  point:  We 
know,  if  we  wish  to  retard  the  melting  between  two  different 
mixtures,  we  must  put  an  heavy  split  of  coke  between  them. 
By  so  doing  we  keep  the  iron  high  above  the  melting  zone, 
until  a  part  of  the  coke  is  burnt  away,  when  the  top  part 
or  last  four  inches  of  the  coke  wil  drop  to  a  point  where  it 
can  melt  the  iron  above  it. 

It  is  just  the  same  with  the  high  coke  bed.  It  is  only 
the  last,  or  top  four  inches  that  does  the  real  melting,  and 
like  the  heavy  split  of  coke,  even  that  four  inches  will  not 
melt  iron  until  it  drops  to  the  real  melting  zone,  and  then 
it  will  only  melt  so  miich<  so  if  burdene'cj  .with  an  extra  heavy 

'.55  ' 


first  charge  of  iron,  the  bed  proper  is  bound  to  suffer,  and 
can  only  be  built  up  again  at  the  expense  of  irregular  iron, 
and  extra  coke,  which  would  not  be,  if  all  the  charges  had 
been  made  as  near  as  possible  what  they  should  be,  accord- 
ing to  the  size  of  the  cupola.  It  is  not  very  good  cupola 
practice  to  let  the  iron  soak  too  long  in  the  cupola  before 
starting  the  blast,  as  I  believe  the  iron  absorbs  more  or  less 
sulphur  from  the  fuel  during  that  time.  It  is  a  fact,  that 
"converter  steel"  men,  if  they  have  to  make  castings  to 
strict  specifications,  will  not  use  first  charges  for  that  class  of 
work  if  they  can  help  it.  The  reason,  that  sulphur  always 
runs  higher  in  first  charges  than  in  the  following  charges. 
Fairly  good  practice  calls  for  the  fire  to  be  started  about  one 
hour  before  charging.  As  charging  will  take  from  three 
quarters  to  one  hour,  the  blast  should  then  be  put  on  as 
soon  as  possible.  If  the  bed  is  the  right  height,  the  iron 
will  begin  to  drop  within  a  minute  or  so,  and  will  be  droping 
quite  fast  within  three  minutes,  as  can  be  seen  through 
tuyer  glasses. 

Although  I  have  mentioned  that  the  melting  zone  will 
average  about  20  inches  above  the  tuyers,  I  do  not  mean 
that  to  be  the  height  of  the  bed.  We  may  have  to  make 
it  30  inches,  or  even  more,  because  the  bed  will  settle  from 
8  to  12  inches  as  soon  as  the  first  charge  of  iron  is  dumped 
on  it — that  point  will  have  to  be  settled  by  the  time  it  takes 
the  iron  to  begin  to  drop  after  the  blast  is  put  on,  the  melting 
zone  being  located  entirely  by  the  force  of  the  blast.  If 
the  blast  is  high  and  strong,  so  will  the  melting  zone  be 
located  high,  so  make  the  coke  bed  rather  high  at  first  then 
reduce  till  you  find  proper  height  by  above  instructions. 


56 


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